How to hold a tap in the tailstock?

I just use a standard drill chuck -- just for the reason you pointed out, the the tap will slip when it meets the bottom of the hole, or when the resistance gets to much (taps are hard and wont mar like a drill bit). I do have variable speed and this is done very slow. At the first slip, I reverse and will usually try again and get a thread or two more, if needed then I finish the threads with conventional means by hand. (use lots of thread cutting oil!)
 
If you get the chance could you snap a pic of your setup so I can wrap my brain around it?

I am using a 12x36 HF and was trying to tap a 5/16 bolt into the end of a shaft.

Thanks

Take a look at this video: http://www.youtube.com/watch?v=KBrrVnYBPOQ&feature=relmfu

He shows the spring punch in a drill press, but the method is the same in a lathe.

Here is a nice plan. It's the first project I did! http://www.projectsinmetal.com/free-project-plan-spring-center-metal-lathe-mill/
 
Here is a few pics for you. I am assuming your just trying to get you tap started straight. 20120921_112610_zpsab907839.jpg

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These tap holders are roughly under 10 bucks each, the spring loaded punch is also under 10 bucks. Hardly worth the effort to make one. For large taps, I use a my 3 jaw 3 inch chuck, I can get a pretty good grip with that.

The one pic just shows different ends on the taps. Not all will take the point directly, and the reason I use the tap holder with T-handles to get them started. Once your in a few turns, put what ever handle you want on.

There is also special chucks meant for holding taps on the square end, but I dont have one. But if your tapping under power, then thats another deal all together.

Hope this helps some


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20120921_113404_zps37557787.jpg

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20120921_114310_zpsc28d8a74.jpg

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I was originally trying to tap under power, I am learning from this thread that is not advisable. Best to do it by hand it sounds like.
 
Jimbob

Nice job you did on your spring loaded tap holder. Thats a real nice looking piece of work.

Tapping under power is ok to do. I wouldnt recommend doing it till you get used to tapping with out power. Someone on this site made a slick tap handle/holder, it looked like a good plan for under power tapping. In the design, it the tap got tight it would slip. Atleast I think it was here. If anyone remembers the thread, point us to it.
Pontiac, if your wanting to tap under power, you can still do it using a typical handle, with lots of care I might add. I do it on my machine. I rest the handle on a wood way cover that locks over the ways. The other thing you will need, is a good spring loaded setup like Jimbob has made. The big problem with tapping under power is if things get to tight, then come the sound, Snap: and there goes the whole job. Your best to start and finish by hand. Unless you have a run of the same parts to tap.
 
Dang, jimbob. Did you come over and steal mine?

photo 2.JPG
 
When I use a drill chuck in the tailstock for tapping, I turn the spindle by hand. I'm just interested in getting the tap started straight. After there are a few threads cut, I remove the tap from the chuck and then use the regular tap handle to run the tap to depth.

By doing it all by hand power, you are able to back up regularly to break the chip. Every now and then, remove the tap to clear the chips.
 
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